Retrofitting a Goliath of The

COVER STORY Pacific Dawn retrofit team from Inter-Marine. Retrofitting a goliath of the sea An Australian heavy marine specialist recently claimed a successful world-first refrigerant retrofit onboard Australia’s first super cruise liner. In doing so, the company ensured the ship’s numerous HVAC&R systems are future-proofed as it continues to sail the South Pacific, writes Sean McGowan. Anyone who has ever had the pleasure of taking a holiday on a super cruise liner can attest to both the enormity and grandeur of these vessels. Australia’s own MV Pacific Dawn is no exception. Designed by renowned Italian architect Renzo Piano and built by the Fincantieri shipyard in Monfalcone, the Pacific Dawn was originally named Regal Princess by former UK Prime Minister Margaret Thatcher before its maiden voyage from Fort Lauderdale in the US, to the Caribbean in 1991. The ship has since collected more stamps in its passport than even the most intrepid traveler. It alternated between cruises to the Caribbean during northern hemisphere winters to Alaska during their summer, before heading to Australia earlier this decade. In 2003, it returned to the Mediterranean before again sailing out of New York for a period of time, until in 2007 it was transferred permanently to the P&O Cruises Australia fleet, and subsequently renamed Pacific Dawn by Olympic gold medalist Cathy Freeman. Accommodating approximately 2,680 passengers and crew, the 70,000 tonne cruise liner has since enjoyed two years in service sailing to various destinations across the Pacific out of Brisbane. Pacific Dawn in Sydney Harbour Measuring some 245m in length, it is almost one and half times the length of Sydney’s ANZ Stadium. It comprises 14 decks featuring a two-storey, 740-seat Five reciprocating DX (direct exchange) critical air conditioning plants also show lounge, nine bars and lounges, five restaurants, and 795 rooms – more service the main electrical switch, ECR and communications rooms, as well as the than any hotel in Sydney. onboard hospital. As such, the refrigerant piping network is vast, running from Deck 2 to all galleys, bars, pantries and critical rooms located across the vessel. While holiday makers enjoy the ship’s amenities, behind the scenes is just as impressive, featuring a range of critical HVAC&R infrastructure. This includes These systems had all operated on HCFC R22 refrigerant until the Pacific Dawn six freezer rooms totaling 600m³ in space, cooled to – 20°C by twin Stal Screw went into dry dock earlier this year for refurbishment, where the decision to condensing units, while another set of condensing units cool 24 cool rooms retrofit them was made. This would ensure the ship’s systems were compliant with an incredible 2,620m³ capacity to 4°C. This is in addition to a range of ahead of the planned R22 phase-out, as well as provide longevity and avoid any refrigeration systems serving the ship’s galley, pantry and bars. compromise on existing capacity or efficiency. 8 n HVAC&R Nation n September 2010 n www.hvacrnation.com.au COVER STORY Review of compatibility is a key diagnosis during refrigerant retrofits, and includes all aspects of the system, from the type of oil, return suitability to the compressors, compressor type, evaporator design and expansion type. System hardware and age was also a consideration in regards to elastomers and plastomers. “A lot of pre-retrofit work was carried out before the event in the cool and freezer rooms to prepare the systems for the retrofit,” says Blackburn. “There were approximately 120 TX (thermal expansion) valves that were checked, thermal bonding improved, evaporators de-iced, and elastomers checked or replaced.” Comprehensive leak testing was also conducted, with base-line recordings for temperatures, pressures and superheats taken – all carried out during the normal daily operations of the systems at sea. According to Blackburn, the short turnaround of the retrofit for the critical systems was immediately identified as a potential “show-stopper” due to the large food and beverage inventory on board. As such, this base-line performance recording was critical while the system was still performing on its design refrigerant, and meant that the ship’s catering and cooking staff needed to be engaged in the process. Detailed time line gant charts were established A member of Inter-Marine working on the retrofit. before the works in conjunction with relevant ship catering and cooking staff and the Inter-Marine Charged with the task of retrofitting the refrigerant Following receipt of the brief, Inter-Marine quickly service team. was Sydney-based heavy marine specialist set about seeking an appropriate replacement Inter-Marine (a sister company to Inter-Chillers) refrigerant for the R22. “During the planning stage, we understood that to preserve food stock we had to have part who was engaged to first review the vessel’s “It is more practical and convenient for a vessel R22-contained onboard systems, and make a ownership of the project from the ship’s staff to carry minimal types of refrigerant from a in respect to room isolation. Meetings were recommendation for the replacement refrigerant. procurement and storage point of view,” explains held with key ship management in charge of Blackburn, adding that while having successfully According to managing director Graeme Blackburn, the provisions stores, food preparation and trialled R417C as a R22 replacement in various it is Inter-Marine’s ability to specialise in quick delivery departments in respect to cooking systems, the firm had experienced some retrofits turnaround dry dockings, where its workforce and meal times,” Blackburn explains, adding where performance was not to expectation. can number up to 130 technicians working that about 950 crew and contractors were to around the clock within a short docking period, be living on board during the dry dock. that has seen it become a preferred supplier “ It is more practical and Systems that were deemed non-critical were of P&O Cruises Australia. convenient for a vessel to carry planned to have works carried out during normal hours. Critical systems would have technicians “Cruise ship dry docking can be the most minimal types of refrigerant working around the clock. Due to the complex demanding engagement undertaken, as they from a procurement and nature of the critical plants, two teams of three consist of strict and tight timelines – the ship must storage point of view” technicians each were arranged to work 12 hourly have all projects completed within the docking shifts, while standby “reserve” technicians working period due to its ongoing cruising itinerary,” elsewhere on board could be called upon in the he explains. “In the Pacific Dawn’s instance, we wanted the event of any unforeseen circumstances. vessel to operate on one common refrigerant “[Therefore it] is one window of opportunity throughout, and selected MO99 after studying within a two-year operational period that presents its compatibility to all candidate systems Reclaim and an excellent time to conduct works that may be and components on board.” otherwise difficult to conduct during service.” best practice MO99 is a new Isceon refrigerant designed as an R22 replacement. Among the characteristics making Perhaps the most challenging aspect of the retrofit Planning for it a candidate for this retrofit was that although a was the requirement for quick refrigerant reclaim, zeotrope, it is close to being an azeotrope. which would be a key component for success on the expected the critical systems. As such, larger access valves Although claimed to be a simple drop-in were installed in various points on the systems, and unexpected refrigerant, retrofitting it on a ship naturally particularly in the liquid lines, as reclaiming throws up different variables. The Inter-Marine With just 12 days available during dry dock, refrigerant in the liquid phase would prove to be team had to contend with four main challenges: the quickest transfer method. planning for a ship’s refurbishment can begin up to diagnosing the system component compatibility; six months prior – a period necessary to ensure all the short turn-around; the issue of refrigerant “Quick retrofits can only be achieved by minimising procurement and resources are in place, including reclaim; and conducting the retrofit live with the reclaiming stage and vacuum stage,” explains contingency plans should something go wrong. $750,000 worth of provision stock in the rooms. Blackburn. “We work to best practice and had a target www.hvacrnation.com.au n September 2010 n HVAC&R Nation n 9 COVER STORY A $100,000 self-contained 20 foot shipping container was also converted into a mobile workshop and storage facility, and craned on board the vessel during docking to provide the Inter- Marine team with quick access to tools, service equipment and spare parts. This facility was seen as critical because of the around-the-clock nature of the works. Delivering on time The entire retrofit required approximately 500 kg of MO99 refrigerant, supplied by Airefrig Australia. Although the project was completed largely without incident due to fastidious planning, a number of lessons were still learned about what is considered a world-first shipping refrigerant retrofit. “Although new generational refrigerants are deemed to be compatible with polyester synthetic and mineral-based oil, plastomers and elastomers, the experience gleaned [on this project] is that aged gaskets that may not be leaking when tested in the pre-retrofit phase should not be trusted,” says Blackburn. “ Quick retrofits can only be achieved by minimising the reclaiming stage and vacuum stage” “Disturbing an existing aged system from positive pressure to high vacuum can create joint leaks, so proactive joint integrity needs to be conducted during the pre-retrofit and base-line phases.” Upon completion of the retrofit, close monitoring was carried out on all key points, temperatures, pressures, superheats and oil returns as each system was brought slowly back online, stage by stage, until full load was achieved.

Load more